Brassinosteroids play diverse roles in plant growth and development. Plants deficient in brassinosteroid （BR） biosynthesis or defective in signal transduction show many abnormal developmental phenotypes, indicating ...Brassinosteroids play diverse roles in plant growth and development. Plants deficient in brassinosteroid （BR） biosynthesis or defective in signal transduction show many abnormal developmental phenotypes, indicating the importance of both BR biosynthesis and the signaling pathway in regulating these biological processes. Recently, using genetics, proteomics, genomics, cell biology, and many other approaches, more components involved in the BR signaling pathway were identified. Furthermore, the physiological, cellular, and molecular mechanisms by which BRs regulate various aspects of plant development, are being discovered. These include root development, anther and pollen development and formation, stem elongation, vasculature differentiation, and cellulose biosynthesis, suggesting that the biological functions of BRs are far beyond promoting cell elongation, This review will focus on the up-to-date progresses about regulatory mechanisms of the BR signaling pathway and the physiological and molecular mechanisms whereby BRs regulate plant growth and development.展开更多
This study observes the therapeutic detoxification of quercetin, a well-known flavonoid, against carbon tetrachlodde （CCI4） induced acute liver injury in vivo and explores its mechanism. QuerceUn decreased CCI4-incr...This study observes the therapeutic detoxification of quercetin, a well-known flavonoid, against carbon tetrachlodde （CCI4） induced acute liver injury in vivo and explores its mechanism. QuerceUn decreased CCI4-increased serum activities of alanine and aspartate aminotransferases （ALT/AST） when orally taken 30 min after CCI4 intoxica- tion. The results of a histological evaluation further evidenced the ability of quercetin to protect against CCI4-induced liver injury. Quercetin decreased the CCI4-increased malondialdehyde （MDA） and reduced the glutathione （GSH） amounts in the liver. It also reduced the enhanced immunohistochemical staining of the 4-hydroxynonenal （4-HNE） in the liver induced by CCI4. Peroxiredoxin （Prx） 1, 2, 3, 5, 6, thioredoxin reductase 1 and 2 （TrxRl/2）, thioredoxin 1 and 2 （Trxl/2）, nuclear factor erythroid 2-related factor 2 （Nrf2）, and heme oxygenase-1 （HO-1） all play critical roles in maintaining cellular redox homeostasis. Real-time polymerase chain reaction （PCR） results demonstrated that quercetin reversed the decreased mRNA expression of all those genes induced by CCI4. In conclusion, our results demonstrate that quercetin ameliorates CCI4-induced acute liver injury in vivo via alleviating oxidative stress injuries when orally taken after CCI4 intoxication. This protection may be caused by the elevation of the antioxidant capacity induced by quercetin.展开更多
The electrical microenvironment plays an important role in bone repair.However,the underlying mechanism by which electrical stimulation(ES)promotes bone regeneration remains unclear,limiting the design of bone microen...The electrical microenvironment plays an important role in bone repair.However,the underlying mechanism by which electrical stimulation(ES)promotes bone regeneration remains unclear,limiting the design of bone microenvironment-specific electroactive materials.Herein,by simple co-incubation in aqueous suspensions at physiological temperatures,biocompatible regenerated silk fibroin(RSF)is found to assemble into nanofibrils with aβ-sheet structure on MXene nanosheets,which has been reported to inhibit the restacking and oxidation of MXene.An electroactive hydrogel based on RSF and bioencapsulated MXene is thus prepared to promote efficient bone regeneration.This MXene/RSF hydrogel also acts as a piezoresistive pressure transducer,which can potentially be utilized to monitor the electrophysiological microenvironment.RNA sequencing is performed to explore the underlying mechanisms,which can activate Ca^(2+)/CALM signaling in favor of the direct osteogenesis process.ES is found to facilitate indirect osteogenesis by promoting the polarization of M2 macrophages,as well as stimulating the neogenesis and migration of endotheliocytes.Consistent improvements in bone regeneration and angiogenesis are observed with MXene/RSF hydrogels under ES in vivo.Collectively,the MXene/RSF hydrogel provides a distinctive and promising strategy for promoting direct osteogenesis,regulating immune microenvironment and neovascularization under ES,leading to re-establish electrical microenvironment for bone regeneration.展开更多
Molecular ferroelastics with the natural features of mechanical flexibility and switchable spontaneous strain have attracted widespread attention in the scientific community due to their potential applications in tuna...Molecular ferroelastics with the natural features of mechanical flexibility and switchable spontaneous strain have attracted widespread attention in the scientific community due to their potential applications in tunable gratings,flexible memorizers,strain sensors,and intelligent actuators.However,most designs of molecular ferroelastics remain in the stage of blind exploration,posing a challenge to achieve a functional ferroelastic more effectively.Herein,we have successfully obtained a molecular ferroelastic,[Me_(2)NH(CH_(2))_(2)NH_(3)](ReO_(4))_(2)(Me_(2)NH(CH_(2))_(2)NH_(3)=N,N-dimethylethylenediammonium),under the guidance of the mono-/double-protonation strategy.The_double-protonated[Me_(2)NH(CH_(2))_(2)NH_(3)](ReO_(4))_(2) undergoes a paraelastic-ferroelastic phase transition with the Aizu notation of 2/mFi at 322 K.Meanwhile,the theoretical calculation and experimental measurement simultaneously show that[Me_(2)NH(CH_(2))_(2)NH_(3)](ReO_(4))_(2) possesses good mechanical flexibility,because its elastic modulus(E)of 8.26 GPa and hardness(H)of 0.45 GPa are smaller than the average values of organic crystals(E of 12.05 GPa and H of 0.5 GPa),which makes it promising to apply in wearable pressure sensors,implantable medical sensors,high-precision tuners,etc.This work further enriches the molecular ferroelastic family and demonstrates that mono-/double-protonation is one of the effective molecular modification strategies for designing ferroelastics.展开更多
文摘Brassinosteroids play diverse roles in plant growth and development. Plants deficient in brassinosteroid （BR） biosynthesis or defective in signal transduction show many abnormal developmental phenotypes, indicating the importance of both BR biosynthesis and the signaling pathway in regulating these biological processes. Recently, using genetics, proteomics, genomics, cell biology, and many other approaches, more components involved in the BR signaling pathway were identified. Furthermore, the physiological, cellular, and molecular mechanisms by which BRs regulate various aspects of plant development, are being discovered. These include root development, anther and pollen development and formation, stem elongation, vasculature differentiation, and cellulose biosynthesis, suggesting that the biological functions of BRs are far beyond promoting cell elongation, This review will focus on the up-to-date progresses about regulatory mechanisms of the BR signaling pathway and the physiological and molecular mechanisms whereby BRs regulate plant growth and development.
基金Project supported by the "Shu Guang" Project from Shanghai Municipal Education Commission and Shanghai Education Development Foundation(No.13SG43)the National Natural Science Foundation of China(No.81322053)the Program for New Century Excellent Talents in University(No.NCET-11-1054),China
文摘This study observes the therapeutic detoxification of quercetin, a well-known flavonoid, against carbon tetrachlodde （CCI4） induced acute liver injury in vivo and explores its mechanism. QuerceUn decreased CCI4-increased serum activities of alanine and aspartate aminotransferases （ALT/AST） when orally taken 30 min after CCI4 intoxica- tion. The results of a histological evaluation further evidenced the ability of quercetin to protect against CCI4-induced liver injury. Quercetin decreased the CCI4-increased malondialdehyde （MDA） and reduced the glutathione （GSH） amounts in the liver. It also reduced the enhanced immunohistochemical staining of the 4-hydroxynonenal （4-HNE） in the liver induced by CCI4. Peroxiredoxin （Prx） 1, 2, 3, 5, 6, thioredoxin reductase 1 and 2 （TrxRl/2）, thioredoxin 1 and 2 （Trxl/2）, nuclear factor erythroid 2-related factor 2 （Nrf2）, and heme oxygenase-1 （HO-1） all play critical roles in maintaining cellular redox homeostasis. Real-time polymerase chain reaction （PCR） results demonstrated that quercetin reversed the decreased mRNA expression of all those genes induced by CCI4. In conclusion, our results demonstrate that quercetin ameliorates CCI4-induced acute liver injury in vivo via alleviating oxidative stress injuries when orally taken after CCI4 intoxication. This protection may be caused by the elevation of the antioxidant capacity induced by quercetin.
基金This work was supported by National Natural Science Foundation of China,China(No.82272457,81972508,82172738)“Technology Innovation Action Plan”of Science and Technology Commission of Shanghai Municipality,China(21S11902700)+3 种基金Natural Science Foundation of Shanghai,China(21ZR1412300)Shanghai Talent Development Fund,China(2020067)Shanghai“Rising Stars of Medical Talent”Youth Development Program,China(Youth Medical Talents-Specialist Program,[2020]087),Shanghai Sailing Program,China(No.19YF1406800)Xiamen Medical and Health Guidance Project,China(3502Z20214ZD1078).
文摘The electrical microenvironment plays an important role in bone repair.However,the underlying mechanism by which electrical stimulation(ES)promotes bone regeneration remains unclear,limiting the design of bone microenvironment-specific electroactive materials.Herein,by simple co-incubation in aqueous suspensions at physiological temperatures,biocompatible regenerated silk fibroin(RSF)is found to assemble into nanofibrils with aβ-sheet structure on MXene nanosheets,which has been reported to inhibit the restacking and oxidation of MXene.An electroactive hydrogel based on RSF and bioencapsulated MXene is thus prepared to promote efficient bone regeneration.This MXene/RSF hydrogel also acts as a piezoresistive pressure transducer,which can potentially be utilized to monitor the electrophysiological microenvironment.RNA sequencing is performed to explore the underlying mechanisms,which can activate Ca^(2+)/CALM signaling in favor of the direct osteogenesis process.ES is found to facilitate indirect osteogenesis by promoting the polarization of M2 macrophages,as well as stimulating the neogenesis and migration of endotheliocytes.Consistent improvements in bone regeneration and angiogenesis are observed with MXene/RSF hydrogels under ES in vivo.Collectively,the MXene/RSF hydrogel provides a distinctive and promising strategy for promoting direct osteogenesis,regulating immune microenvironment and neovascularization under ES,leading to re-establish electrical microenvironment for bone regeneration.
基金financially supported by Southeast University and the National Natural Science Foundation of China(Grant Nos.21991141 and 22371258).
文摘Molecular ferroelastics with the natural features of mechanical flexibility and switchable spontaneous strain have attracted widespread attention in the scientific community due to their potential applications in tunable gratings,flexible memorizers,strain sensors,and intelligent actuators.However,most designs of molecular ferroelastics remain in the stage of blind exploration,posing a challenge to achieve a functional ferroelastic more effectively.Herein,we have successfully obtained a molecular ferroelastic,[Me_(2)NH(CH_(2))_(2)NH_(3)](ReO_(4))_(2)(Me_(2)NH(CH_(2))_(2)NH_(3)=N,N-dimethylethylenediammonium),under the guidance of the mono-/double-protonation strategy.The_double-protonated[Me_(2)NH(CH_(2))_(2)NH_(3)](ReO_(4))_(2) undergoes a paraelastic-ferroelastic phase transition with the Aizu notation of 2/mFi at 322 K.Meanwhile,the theoretical calculation and experimental measurement simultaneously show that[Me_(2)NH(CH_(2))_(2)NH_(3)](ReO_(4))_(2) possesses good mechanical flexibility,because its elastic modulus(E)of 8.26 GPa and hardness(H)of 0.45 GPa are smaller than the average values of organic crystals(E of 12.05 GPa and H of 0.5 GPa),which makes it promising to apply in wearable pressure sensors,implantable medical sensors,high-precision tuners,etc.This work further enriches the molecular ferroelastic family and demonstrates that mono-/double-protonation is one of the effective molecular modification strategies for designing ferroelastics.
